Internet Protocol
In this section we will explore the Internet Protocol (IP) to discover how IP enables the applications running above the transport layer (UDP/TCP) to utilize any of the different datalink layers available.
5.2 Internet Protocol
The Internet Protocol (IP) is the network layer protocol of the TCP/IP protocol suite. IP allows the applications running above the transport layer (UDP/TCP) to use a wide range of heterogeneous datalink layers. IP was
Figure 5.17: Computation of the routing table
designed when most point-to-point links were telephone lines with modems. Since then, IP has been able to use Local Area Networks (Ethernet, Token Ring, FDDI,...), new wide area data link layer technologies (X.25, ATM, Frame Relay,...) and more recently wireless networks (802.11, 802.15, UMTS, GPRS,...). The flexibility of IP and its ability to use various types of underlying data link layer technologies is one of its key advantages.
Figure 5.18: IP and the reference model
The current version of IP is version 4 specified in RFC 791. We first describe this version and later explain IP version 6, which is expected to replace IP version 4 in the not so distant future.
Source: Olivier Bonaventure, https://s3.amazonaws.com/saylordotorg-resources/wwwresources/site/wp-content/uploads/2012/02/Computer-Networking-Principles-Bonaventure-1-30-31-OTC1.pdf This work is licensed under a Creative Commons Attribution 3.0 License.